Can not remove delegate from appointment changes in outlook

One of my users had an assistant that received all schdule
changes on his calander. After she left the company her AD
account and exchange mail box was removed and purged. Now every
time someone changes his calender or sends him an invitation
they get an "Undeliverable" email from System Admin
saying the user's (old assistant) email account dose not
exist.

I have removed all delegation from the current users account in
outlook and AD dose not show anyone as a delegate or to receive
emails on his behalf. Does anyone know what is going on here or
what im missing?

Yes, I did mean the rules in Outlook. The only other thing I can think
of is a vb script in Outlook or on the exchange server. Oh, is this
happening to recurring events? There is a forward feature in the Actions
menu. If this is set any changes to the event will be forwarded.

Hi That1Guy,
Have u tried outlook switches to clean information which are sometime gets cached and needs u to run outlook switches to clean those. make sure you check that user doesn't have rules setup.
outlook /cleanrules /cleanfreebusy /cleanviews
Or also check user outlook profile where we grant delegation the â€œSend all responses to my delegateâ€ check box can remain checked although seemingly inactive. But you can check by adding a name into the delegate space, you can than un-check that box then remove the ghost delegate name.
Regards,
HB